2133865 has 4 divisors (see below), whose sum is σ = 2560644. Its totient is φ = 1707088.

The previous prime is 2133839. The next prime is 2133899. The reversal of 2133865 is 5683312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 870489 + 1263376 = 933^2 + 1124^2 .

It is a cyclic number.

It is not a de Polignac number, because 2133865 - 2²¹ = 36713 is a prime.

It is a Duffinian number.

2133865 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 213382 + ... + 213391.

It is an arithmetic number, because the mean of its divisors is an integer number (640161).

2^2133865 is an apocalyptic number.

It is an amenable number.

2133865 is a deficient number, since it is larger than the sum of its proper divisors (426779).

2133865 is an equidigital number, since it uses as much as digits as its factorization.

2133865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 426778.

The product of its digits is 4320, while the sum is 28.

The square root of 2133865 is about 1460.7754789837. The cubic root of 2133865 is about 128.7426111950.

The spelling of 2133865 in words is "two million, one hundred thirty-three thousand, eight hundred sixty-five".